textproduct: Albany

WHAT HAS CHANGED

No significant changes with this forecast update.

KEY MESSAGES

1) Temperatures trend above normal this week with mostly dry weather through Wednesday before chances for rain increase Thursday into Thursday night as a cold front arrives. Depending on if and when the front slows down, there is a low to medium chance in rain showers continuing into Friday and the weekend.

DISCUSSION

KEY MESSAGE 1...

A 1030hPa high settles just off the coast today, giving us another day of dry and pleasant fall weather with south- southwest flow supporting weak warm air advection. Even with some increasing mid and high level clouds as moisture spills over the approaching ridge, temperatures will still likely warm 10-15 degrees above normal into the low to mid 60s. Ridging centered in the Ohio Valley amplifies and continues building eastward tomorrow, sending a weak warm front into the Northeast. Overall moisture and forcing continue to appear rather weak with latest NBM probabilistic guidance limiting chances for at least 0.01" of rain to the southern/western Adirondacks and Upper Hudson Valley with chances ranging from 20-40% tomorrow afternoon. The front lifts north of eastern NY by tomorrow evening, with the ridge axis and warm sector shifting overhead into Wednesday. There is increasing confidence that Wednesday will be a beautiful day as large scale riding supports mainly sunny skies and the incoming 850hPa isotherms ranging 2 to 2.5 standard deviations above normal per the NAEFS and ENS likely supports well above normal temperatures. In fact, the latest NBM probabilistic guidance shows a 40 to 80% chance for highs to meet or exceed 70 degrees for much of eastern NY and western New England outside the higher terrain areas.

Temperatures remain mild into Wednesday night with well above normal temperatures likely continuing into Thursday as a cold front slides eastward. The boundary is associated with a broad and weakening positively tilted trough over the Upper Midwest/Great Lake with the parent low occluding as the front moves into the Northeast. Despite the weakening forcing and upper level dynamics, the moisture transport ahead of the front and thermal gradient along the boundary should be sufficient to support our first measurable rainfall event in three weeks! The front looks to reach eastern NY by Thursday afternoon and heads into western New England by Thursday evening as the weakened parent shortwave interacts and potentially phases with a northern stream shortwave in southern Canada. Latest ensembles and clusters still show a split solution regarding when the phasing occurs which will determine if the front slows down while it is still overhead or if it will have a chance to escape into New England before slowing down. There is a large enough spread in the guidance to support widespread likely POPS Thurs night with likely POPs focused along and east of the Hudson on Friday before trending lowering by Saturday. Latest guidance shows there is a 30 to 70% chance for at least a half inch of much needed rain between 7am Thursday and 7am Friday for much of the area. Once the two shortwaves phase, there is good consensus in a secondary low developing along the boundary resulting in more widespread rain; however, the latest trends suggest this may occur when the boundary is far enough to our east to keep most of the impacts in New England. Even still, unsettled conditions look to continue over the weekend as the upper level parent low moves overhead supporting additional scattered showers and cool air advection that trend temperatures back towards normal.

AVIATION /18Z MONDAY THROUGH SATURDAY/

Through 18z Tuesday...VFR conditions are expected to prevail through the 24 hour TAF period. Fog is not anticipated at any sites tonight due to increasing mid level clouds around 10 kft AGL, especially from KALB and KPSF north to KGFL. Winds will initially be southerly around 7-11 kt, becoming variable at less than 5 kt tonight.

Outlook...

Tuesday Night: No Operational Impact. NO SIG WX. Wednesday: No Operational Impact. NO SIG WX. Wednesday Night: No Operational Impact. NO SIG WX. Thursday: High Operational Impact. Breezy. Likely RA. Thursday Night: High Operational Impact. Likely RA. Friday: Moderate Operational Impact. Likely RA. Friday Night: Moderate Operational Impact. Likely RA. Saturday: Moderate Operational Impact. Chance of RA.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...None. MA...None. VT...None.